Attwood 500 GPH 12V Shower Sump MK2 System

The Attwood 500 GPH 12V Shower Sump MK2 System is a compact gray-water collection and discharge system for marine showers and other compatible drains. Its integrated 500 GPH pump handles lower-volume sump applications while keeping drain water contained in an enclosed box before discharge.

The MK2 housing is designed for efficient flow through the sump and includes a removable snap-on lid for cleaning and inspection. A gasketed cover helps control overflow, and the built-in air vent allows trapped air to escape so the pump can cycle more reliably. This 500 GPH version draws 1.4A and uses a 3A fuse, making it the lower-current option in the MK2 pair.

Before installation, confirm the drain-hose connections, discharge route, 12V electrical supply, fuse protection, mounting location, and access to the lid. Keep the sump interior and strainer area clean, secure all hose connections, and test the automatic pump cycle with clean water after installation.

• 500 GPH pump capacity for compatible shower and gray-water drainage
• 1.4A current draw with 3A fuse requirement
• Snap-on lid allows routine cleaning and service access
• Integrated vent helps reduce airlock conditions inside the sump

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